1. Field of the Invention
The present invention relates to a device for tensioning a side tarpaulin on a mounting structure, such as a vehicle superstructure, and, more particularly, is concerned with a side tarpaulin tensioning device having a tightener that will stay secured to an abutment element independent of the tension exerted on the side tarpaulin.
2. Description of the Prior Art
It is known to place and hold a side tarpaulin under tension on a vehicle superstructure by securing to an abutment element on the vehicle superstructure at least one side tarpaulin tightener being attached on a lower end of the side tarpaulin. One prior art device providing side tarpaulin tensioning in this way is disclosed in German patent document No. DE 44 15 042 C1. In the device of this German patent document, a lower edge of an outer frame of the vehicle superstructure serves as the abutment element for the tightener. The tightener itself is connected with the side tarpaulin via a belt which can be adjusted in length and is disposed on the outside of the side tarpaulin. The tightener includes a base element on which a hook is formed which, for tensioning the side tarpaulin, can be secured in position, for example, on the lower edge of the outer frame of the vehicle superstructure. The tightener also includes a tension lever pivotally articulated to the base element. By pivoting the tension lever from an open position to a closed position relative to the base element, the belt on the side tarpaulin and thus the side tarpaulin itself are placed under tension. The tightener further includes a latch pivotally mounted on the tension lever which is moved to a latched position behind a projection on the base element to retain the tension lever in its closed position. Other, overcenter type, tensioners are known in the prior art in which it is not necessary to provide additional latching in order to retain the tension lever in the closed position.
By extending the hook formed on the base element of the tightener behind the stationary abutment element on the vehicle superstructure and by applying tensile stress onto the side tarpaulin using the tension lever, the tightener is secured in the proper position on the stationary abutment element of the vehicle superstructure. Also, through the action of the applied tensile stress, the hook is retained in the proper position in which it extends behind the stationary abutment element.
A disadvantage of such type of side tarpaulin tightener is that upon a weakening of the tension force acting upon the side tarpaulin tightener in its closed position, due, for example; to the stretching of the side tarpaulin through temperature increase or also due to degradation, it cannot be ensured that the side tarpaulin tightener will remain in its proper position in which the hook on its base element extends behind the stationary abutment element. Analogous conditions can occur also if, for example, an upper stringer on which the side tarpaulin is retained at the top of the vehicle superstructure becomes deflected downwardly due to loading which can occur in particular when driving through tunnels. If the tension force acting upon such type of side tarpaulin tightener via the side tarpaulin weakens, the tightener can swivel out of its proper position such that its hook no longer extends behind the stationary abutment element and thus the tightener is no longer secured to the vehicle superstructure via the abutment element. The tightener at the lower end of the side tarpaulin then being unsecured may flap about and represent a considerable danger potential.
Another disadvantage of such type of side tarpaulin tightener is that in the open position of the tightener the hook formed on the base element of the tightener is disposed in alignment with the lower end of the outer frame of the vehicle superstructure serving as the stationary abutment element. In order for a side tarpaulin equipped with such side tarpaulin tighteners to be rolled upwardly, it is necessary to ensure that the tighteners are spaced apart from the stationary abutment element to the extent that the hooks are located outside of alignment with the stationary abutment element. Therefore, as a rule, for rolling up a side tarpaulin having such type of tighteners two persons are necessary, with one person actuating the roll-up device and the other person simultaneously pulling the side tarpaulin and the tighteners therewith away from the vehicle superstructure.
Consequently, there is a need for further development of a device of the above type for tensioning a side tarpaulin such that the aforementioned disadvantages are avoided.
The present invention overcomes the aforementioned problems of the prior art by providing a side tarpaulin tensioning device which avoids undesirable detaching of a tightener of the device from a stationary abutment element of the device mounted on the vehicle superstructure and further avoids unintentional catching of the tightener on the stationary abutment element during roll-up of the side tarpaulin.
Accordingly, the present invention is directed to a device for tensioning a side tarpaulin on a mounting structure, such as a vehicle superstructure, which comprises an abutment element attachable to the mounting structure, at least one side tarpaulin tightener separate from the abutment element being attachable to the side tarpaulin and swivelable into the abutment element to a closed position therein so as to serve as a tension lever to apply a desired tension to the side tarpaulin, and a latch mechanism pivotally attached to the side tarpaulin tightener and engageable with the abutment element upon swiveling of the side tarpaulin tightener to the closed position for releasably securing the tightener to the abutment element at the closed position and retaining the tightener at the closed position independent of the tension exerted on the side tarpaulin.
The abutment element of the device is attachable stationarily on the mounting structure and has spaced apart upper and lower portions. The upper portion of the abutment element defines a slide-in pocket open in a downward direction. The lower portion of the abutment element defines a latching edge. The abutment element between the slide-in pocket of the upper portion and the latching edge of the lower portion defines a stop which acts to prevent movement of the side tarpaulin tightener in the downward direction once the tightener is placed in the abutment element at the closed position.
The side tarpaulin tightener of the device includes a base element having spaced apart upper and lower portions and therebetween being adapted for connection to a lower end portion of the side tarpaulin. The upper portion of the base element defines a slide-in section for sliding into the slide-in pocket of the abutment element after which the base element can be swiveled toward the abutment element so as to serve as a tension lever that applies the desired tension to the side tarpaulin and so as to removably place the lower portion of the base element upon the stop of the abutment element such that the base element of the tightener is removably received into the abutment element between the slide-in pocket and the stop thereof.
The latch mechanism of the device includes a closure lever pivotally articulated to the lower portion of the base element and a closure hook attached to the closure lever for undergoing movement therewith. The latch mechanism also includes means for biasing the closure lever and thus the closure hook to move from an unlatched position located away from the latching edge of the lower portion of the base element to a latched position located behind the latching edge so as to secure the base element of the tightener to the abutment element irrespective or independent of the tension applied on the side tarpaulin.
These and other features and advantages of the present invention will become apparent to those skilled in the art upon a reading of the following detailed description when taken in conjunction with the drawings wherein there is shown and described an illustrative embodiment of the invention.